It is known to provide a housing and other support components for a video camera and lens assembly so as to permit the camera and lens assembly to be rotatable about first and second (vertical and horizontal) axes. In this sort of camera supporting structure, the camera and lens assembly can be caused to undergo a panning motion (i.e., rotation about the vertical axis) and a tilting motion (i.e., rotation about the horizontal axis) so as to completely scan a location of interest. Motors are provided for carrying out the panning and tilting motion, and the motors are subject to remote control through known signalling equipment.
A particularly advantageous type of video camera support structure is described in application Ser. No. 08/892,042, filed Jul. 14, 1997. The '042 patent application has a common assignee with the present application, and the disclosure thereof is incorporated herein by reference.
A number of the key components of the camera mounting structure of the '042 patent application are shown in FIGS. 1 and 2 of the present application and will now be briefly described.
In FIG. 1, reference numeral 10 indicates a main housing for the video camera support structure of the '042 patent application. Installed within the main housing 10 is a panning assembly 12 which includes an outer race member and an inner race member, which are not shown separately in FIG. 1. The outer race member is fixedly mounted to the main housing 10 and the inner race member is free to rotate relative to the outer race member about a vertical axis. The two race members of the panning assembly define therebetween a toriodal race plenum (not shown) in which ball bearings are disposed so as to provide for minimal resistance to the rotation of the inner race member relative to the outer race member. A panning motor 14 is also disposed within the housing 10. The panning motor 14 engages a gear (not separately shown in FIG. 1) on the inner race component of the panning assembly 12 and selectively rotates the inner race component about a vertical axis to cause a panning motion.
FIG. 2 shows, in an exploded view, additional portions of the camera support structure, including a yoke bracket formed of bracket-halves 16 and 18. The bracket formed of bracket halves 16 and 18 is mounted to the inner race component of the panning assembly 12 for rotation with the inner race component.
Part-spherical housing sections 20 and 22 are respectively mounted to the bracket halves 16, 18. The housing sections 20, 22 respectively have part-spherical bearings 24, 26 mounted therein. Each of the bearings 24, 26 has a portion which defines the outer boundary of a toroidal ball-bearing race plenum; only the race-defining portion 28 of bearing 26 is shown in FIG. 2. A respective inner race-defining part is mated with the race-defining portions of the bearings 24, 26, so that a complete toroidal bearing race plenum is defined at each of the bearings. (Only the inner race-defining part 30 which corresponds to the bearing 26 is shown in FIG. 2.)
Ball bearings, which are not shown in the drawing, are disposed in the toroidal races defined by the bearings 24, 26 and inner race-defining parts (including part 30), so that the inner race-defining parts are easily rotatable about a horizontal axis.
A camera mounting yoke 32 is in the form of a cage, and is mounted on the inner race-defining parts for rotation therewith about the horizontal axis.. The camera mounting yoke 32 defines an enclosure in which a video camera (not shown) is mounted, so that the camera is rotated about the horizontal axis for tilting motion. It will also be recognized that the yoke 32 rotates about the vertical axis with the yoke bracket for panning motion.
Also shown in FIG. 2 are a motor 34 which drives the yoke 32 for tilting operations and a circuit board 36 which is mounted for movement with the camera yoke 32.
The camera mounting structure disclosed in the above-referenced '042 patent application, and illustrated in part in FIGS. 1 and 2, has advantages in comparison to previous camera dome assemblies, including compact size and ease in assembling and disassembling. This device is being manufactured and distributed by the assignee of the application, Sensormatic Electronics Corporation, under the trademark "Speed Dome Ultra". However, for many surveillance applications a camera that is moveable by remote control is not required, even though it may be desirable that a support structure for mounting a camera in a fixed position be arranged so that the camera's position can be changed easily by hand to adjust the direction of view of the camera.